HOW TO REUSE XAXIDMA BUFFER DESCRIPTORS USING XAXIDMA DEVICE DRIVER?

[joaoamaral]

Hi everyone,

I am currently using XAxiDma Device driver to forward packets from PS to PL. Adapting the examples, i could send a bunch of packets to DMA until i run out of Buffer Descriptors (i am in Scatter Gather Mode). The problem is i need to send an infinite ammount of packets and thus i need to reuse the buffer descriptors somehow... Can anyone tell me how can i make the last BD point back to the first one and reuse all the BDs?

[demarco]

Hi @joaoamaral,

I think you are asking about the AXI DMA IP. AXI DMA does support cyclic mode where you can re-use buffer descriptors. Please review PG021 for details.

https://www.xilinx.com/support/documentation/ip_documentation/axi_dma/v7_1/pg021_axi_dma.pdf

Regards,

Deanna

[bbhatt]

Could you please specify the way in which this can be done as the example provided by xilinx does not work.